PHP Google Keyword Referrer

// take the referer
$thereferer = strtolower($_SERVER['HTTP_REFERER']);
// see if it comes from google
if (strpos($thereferer,"google")) {
	// delete all before q=
    $a = substr($thereferer, strpos($thereferer,"q="));		
	// delete q=
	$a = substr($a,2);
	// delete all FROM the next & onwards
	if (strpos($a,"&")) {
		$a = substr($a, 0,strpos($a,"&"));
	}	
	// we have the results.
	$mygooglekeyword = urldecode($a);
}